With the rapid development of new energy-efficient lighting technologies, especially the LED technology, lighting products have become more efficient and durable. Compared with traditional incandescent lamps, the light conversion efficiency of an LED lamp may be 5 to 10 times higher, and the lifespan of an LED lamp may be 30 to 50 times longer. As a result, energy saving improvements have been well received by commercial and individual users. Moreover, innovative financing methods used in energy-saving projects, such as the Energy Management Contract (EMC) mode, attract more and more attention.
New lighting products such as LEDs have very long lifespans in theory. The lifespan of a lighting product may be defined as the duration during which its light intensity is maintained at, for example, above 70% of the original light intensity. Because there is no practical method to speed up the aging process to measure the lifespan of an LED lighting device, one conventional method is to measure a device's light intensity after 6,000 hours' aging to estimate its lifespan. Due to the rapid development of new energy-efficient LED technologies, one technology may become obsolete even before its product's lifespan can be fully tested. For LED manufacturers, this long test time span may cause problems. On the other hand, for LED device users, unless a device consistently fails in a relatively short time, it may be difficult to measure the real lifespan of a device. It may even be harder to compare the lifespan measurements to the claimed lifespan of a lighting product. For example, one product may claim that it has a lifespan of 25,000 hours. If it failed after 20,000 hours of usage, it would be difficult for the user to show a shorter than claimed lifespan.
As a result, estimating and verifying the lifespan of the new energy-efficient LED devices may be a challenge to device manufacturers and users. The disclosed method and system are directed to solve one or more problems set forth above and other problems